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JunosE 11.3.x IP, IPv6, and IGP Configuration Guide
arp timeout
clear arp
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the destination address are dropped because the router identifies them as spoofed
packets.
In networks with digital subscriber line access multiplexers (DSLAMs), even if you
configure the router to check for spoofed ARP packets, DSLAMs perform this task
instead of the router. If you disable checking for spoofed ARP packets on the router in
such networks, DSLAMs forward the received packets to the router for processing. You
can, therefore, configure the router accordingly, depending on the way in which you
want spoof-checking to be performed.
You cannot configure ARP spoof-checking on interfaces that do do support ARP, such
as loopback interfaces and ATM point-to-point PVCs.
If you disable checking for spoofed ARP packets, all packets received by the router are
processed.
You can reenable checking for spoofed ARP packets on an interface at any time by
using the arp spoof-check command after disabling it.
Example—Shows how to disable spoof-checking for ARP packets received on a Gigabit
Ethernet interface and then reenable it.
host1(config-if)#interface gigabitEthernet 1/1
host1(config-if)#no arp spoof-check
host1(config-if)#arp spoof-check
Use the no version to disable checking for spoofed ARP packets received on a major
IP interface or an IP subinterface.
See arp spoof-check.
Use to specify how long an entry remains in the ARP cache.
You can issue this command only for Fast Ethernet interfaces, Gigabit Ethernet
interfaces, 10-Gigabit Ethernet interfaces, and bridged Ethernet interfaces configured
over ATM 1483.
The default value is 21,600 seconds (6 hours). Use the show config command to
display the current value.
If you specify a timeout of 0 seconds, entries are never cleared from the ARP cache.
Example
host1(config-if)#arp timeout 8000
Use the no version to restore the default value.
See arp timeout
Use to clear dynamic entries from the ARP cache.
To clear a particular entry, specify all of the following:
Copyright © 2010, Juniper Networks, Inc.
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